Cestrum laevigatum

Abstract

DISTRIBUTION: • Originally a native of Brazil. • It is usually found in the moister eastern parts of the country where it grows as an under-storey or at the margins of forests. • Also cultivated as a hedge or windbreak. • Inland it usually grows near rivers or watercourses.

BOTANICAL DESCRIPTION: General: Usually an evergreen, multi-branched shrub of 1 - 2 m, but could grow to a tree of up to 15 m high at the coast. Leaves: The twigs and dark green alternate leaves have an unpleasant smell when crushed. Flowers: A tubular flower with creamy-yellow lobes in small groups in the axils of the uppermost leaves. Closing at night. Fruit: A succulent purple black berry, 1 cm in diameter, which normally contains 6 seeds.

TOXIC PRINCIPLE: The toxic principle is a carboxyatractyloside similar to the poisonous principle of Xanthium strumarium.

SYNDROMES: Chase valley disease – Hepatoxic syndrome without photosensitization.

SYSTEMS AFFECTED: Liver.

CLINICAL SIGNS: • Mainly a cattle problem - liver damage as well as nervous signs. • Green berries and young sprouts most poisonous. • Also garden refuse problem. • High dosage - peracute deaths.

Acute/Subacute poisoning: Gastrointestinal Tract: Salivation; Ruminal stasis; Constipation.

Central Nervous System:Weakness; Ataxia; Stands with an arched back and outstretched neck; Aggressiveness - especially in KwaZulu-Natal; Struggle a lot before death.

NECROPSY: Macroscopical findings: • Liver degeneration as well as haemorrhages and oedema of the gall bladder wall • Haemorrhages - serosal and liver capsule • Hydrothorax, hydropericardium and ascites• Ruminal stasis and constipation - faeces covered with bloody mucous.

HISTOPATHOLOGY: • Centrilobular necrosis and haemorrhage. • Mild bile duct proliferation.

TREATMENT: Supportive and symptomatic. Prevention: Keep stock away from infected veld at danger periods -especially during June and July when it is most toxic.